Clostridium Difficile Vaccine Efficacy Trial

Brief description of study

The Clover trial is evaluating an investigational vaccine that may help to prevent Clostridium difficile infection. Participants in the study are adults 50 years of age and older, who are at risk of developing Clostridium difficile infection. The study will assess whether the vaccine prevents the disease, and whether it is safe and well tolerated. Each subject will receive 3 doses of Clostridium difficile vaccine or placebo and be followed for up to 3 years after vaccination for potential Clostridium difficile infection.